Income Taxes - Unrecognized tax benefits (Details) - USD ($)	6 Months Ended	12 Months Ended
Sep. 24, 2017	Sep. 25, 2016	Mar. 26, 2017
Income Taxes
Gross amount of unrecognized tax benefits	$ 206,300		$ 204,500
Unrecognized tax benefits, net of federal benefit	133,800		147,800
Amount of interest and penalties expense (benefit) related to tax uncertainties recognized, net of federal expense/benefit	24,200	$ 27,000
Cumulative amount of interest and penalties related to tax uncertainties, net of federal expense/benefit	$ 353,900		$ 314,300

Amount of unrecognized tax benefits, net of federal benefit, pertaining to uncertain tax positions taken in tax returns.

No definition available.

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- References

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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- Definition

Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

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- Definition

Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

+ References

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